• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.192-195
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• 2004

Products of gridded surface wind and windstress vectors over the world ocean have been constructed by satellite scatterometer data with highly temporal and spatial resolutions. Even if the ADEOS-II/SeaWinds has supplied surface wind data only for short duration in Apr. to Oct. 2003 to us, it permits us to construct a product with higher resolution together with the Qscat/SeaWinds. In addition to our basic product with its resolution of $1^{\circ}\times1^{\circ}$ in space and daily in time, we try to construct products with $1/2^{\circ}\times1/2^{\circ}$ and semi- and quarter-daily resolution. These products are validated by inter-comparison with in-situ data (TAO and NDBC buoys), and also compared with numerical weather prediction(NWP) ones (NCEP reanalysis). Result reveals that our product has higher reliability in the study area than the NCEP's. For the open ocean regions in the middle and high latitudes where there are no in-situ data, we find that there are clear differences between them. Especially in the southern westerly region of 400-600S, the' wind-stress magnitudes by the NCEP are significantly larger than the others, suggesting that they are overestimated. We also calculate wind-stress curl field that is an important factor for ocean dynamics and focus its spatial character in the northwestern Pacific around Japan. Positive curl areas are found to cover from southwest to northeast in our focus region and almost correspond to the Kuroshio path. It is suggested that the vorticity field in the lower atmosphere is related to the upper oceanic one, and thus an aspect of air-sea interaction process.

• Fisheries and Aquatic Sciences
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• 제20권7호
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• pp.9.1-9.13
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• 2017

Background: Metal-responsive transcription factor-1 (MTF-1) is a key transcriptional regulator playing crucial roles in metal homeostasis and cellular adaptation to diverse oxidative stresses. In order to understand cellular pathways associated with metal regulation and stress responses in Pacific abalone (Haliotis discus hannai), this study was aimed to isolate the genetic determinant of abalone MTF-1 and to examine its expression characteristics under basal and experimentally stimulated conditions. Results: The abalone MTF-1 shared conserved features in zinc-finger DNA binding domain with its orthologs; however, it represented a non-conservative shape in presumed transactivation domain region with the lack of typical motifs for nuclear export signal (NES) and Cys-cluster. Abalone MTF-1 promoter exhibited various transcription factor binding motifs that would be potentially related with metal regulation, stress responses, and development. The highest messenger RNA (mRNA) expression level of MTF-1 was observed in the testes, and MTF-1 transcripts were detected during the entire period of embryonic and early ontogenic developments. Abalone MTF-1 was found to be Cd inducible and highly modulated by heat shock treatment. Conclusion: Abalone MTF-1 possesses a non-consensus structure of activation domains and represents distinct features for its activation mechanism in response to metal overload and heat stress. The activation mechanism of abalone MTF-1 might include both indirect zinc sensing and direct de novo synthesis of transcripts. Taken together, results from this study could be a useful basis for future researches on stress physiology of this abalone species, particularly with regard to heavy metal detoxification and thermal adaptation.

• 한국방재학회 논문집
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• 제6권3호
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• pp.9-16
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• 2006

기존 대부분의 구조물 건전도 모니터링 시스템에서는 제한적인 위치와 범위에서의 변형률 계측이 가능한 국부 변형률 센서를 이용하여 구조물 또는 구조 부재의 부재력을 계측하고 이에 기반하여 구조 안전성을 평가하고 있다. 그러나 실 구조물의 부재력 계측을 통한 안전성 평가는 하중의 크기 및 분포에 대한 불확실성 등의 다양한 이유로 부재 내 최대응력 작용점을 정확하게 파악하기 어렵다. 이러한 경우 구조물의 사이즈에 비하여 센서의 길이가 미소한 국부 변형률 센서를 이용한 안전성 평가의 적절성은 센서의 위치 및 개수에 좌우되는 한계를 가지게 된다. 이러한 한계를 극복하기 위하여 센서의 수를 증가시키면 처리해야하는 데이터의 양과 비용이 증가하게 되므로 현실적인 적용성에 문제점을 가지게 된다. 그러므로 본 연구에서는 이러한 한계와 문제점을 극복할 수 있는 대안으로 장대광변형센서에 의한 평균변형률을 이용한 보-기둥의 부재력 계측 기법을 제시하였다.

• 한국농림기상학회지
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• 제21권2호
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• pp.111-116
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• 2019

세균과 바이러스에 감염된 작물의 생물적 스트레스 탐지를 원격탐지 기술 기반의 열적외 센서를 이용하여 실내 생육 챔버에서 실험하였다. 감염으로 인한 엽온의 증가와 감염 농도에 따른 엽온 차이를 확인했다. 또한 엽온 기반으로 산출한 CWSI 값은 감염 잎에서 증가하였고, 그러한 현상은 육안으로 병징을 발견하기 하루 전에 시작되었다. 따라서 스마트팜 시스템의 작물 모니터링에 열적외 센서를 이용한다면, 병해의 탐지는 물론 피해 등급 평가, 조기 알람 등에 활용될 수 있을 것이다. 하지만 실제 스마트팜 적용을 위해서는 향후 엽온 측정 정확도 향상 기술, 자료 해석 방법, 생물 비생물적 스트레스 구별 알고리즘 연구 등이 추가로 필요할 것이다.

• 한국작물학회지
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• 제69권2호
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• pp.78-87
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• 2024

중간물떼기 기간연장에 따른 벼 생육반응 변화를 분석한 결과는 다음과 같다. 1. 관행 2주간 중간물떼기 대비 중간물떼기 기간이 3주로 연장되었을 경우 수량 및 수량구성요소는 유의한 차이가 없다. 2. 중간물떼기 기간이 4주로 연장되었을 경우 임실률과 영화수, 수량이 급격하게 감소하였다. 3. 중간물떼기가 4주 이상 지속될 경우 NDVI, PRI, CWSI 값이 유의하게 변화하였다. 4. 중간물떼기 기간 연장에 따른 식생지수별 생육지표와의 관계를 분석한 결과 NDVI 대비 CWSI가 약 4일 정도 더 빠르게 한발 스트레스를 감지하였으며 가역적 스트레스 또한 용이하게 확인할 수 있었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2023년도 춘계학술대회
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• pp.105-105
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• 2023

Heavy metals, including lead (Pb) toxicity, are increasing in soil and are considered toxic in small amounts. Pb contamination is mainly caused by industrialization - smelting, mining. Agricultural practices - sewage sludge, pests and urban practices - lead paint. It can seriously damage and threaten crop growth. Pb can adversely affect plant growth and development by affecting the photosystem, cell membrane integrity, and excessive production of reactive oxygen species (ROS) such as hydrogen peroxide (H₂O₂)andsuperoxide(O₂.-). NO is produced via enzymatic and non-enzymatic antioxidants to scavenge ROS and lipid peroxidation substrates in terms of protecting cells from oxidative damage. Thus, NO improves ion homeostasis and confers resistance to metal stress. Our results here suggest that exogenous NO may aid in better growth under lead stress. These enhancements may be aided by NO's ability in sensing, signaling and stress tolerance in plants under heavy metal stress in combination with lead stress. Our results show that GSNO has a positive effect on soybean seedling growth in response to axillary pressure and that NO supplementation helps to reduce chlorophyll maturation and relative water content in leaves and roots following strong burst under lead stress. GSNO supplementation (200 µM and 100 µM) reduced compaction and approximated oxidative damage of MDA, proline and H₂O₂. Under plant tension, a distorted appearance was found in the relief of oxidative damage by ROS scavenging by GSNO application. In summary, modulation of these NO, PCS and prolongation of metal past reversing GSNO application confirms the detoxification of ROS induced by toxic metal rates in soybean. In summary, these NO, PCS and metal traditionally sustained rates of reverse GSNO application confirm the detoxification of ROS induced by toxic metal rates in soybean.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.7-10
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• 2005

Plant water deficiency during drought season causes physiological stress and can be a critical indicator of forest fire vulnerability. In this study, we attempt to analyze the spectral characteristics of water stressed vegetation by using the laboratory measurement on leaf samples and the canopy reflectance spectra extracted from satellite hyperspectral image data. Leaf-level reflectance spectra were measured by varying moisture content using a portable spectro-radiometer. Canopy reflectance spectra of sample forest stands of two primary species (pine and oak) located in central part of the Korean peninsula were extracted from EO-l Hyperion imaging spectrometer data obtained during the drought season in 2001 and the normal precipitation year in 2002. The preliminary analysis on the reflectance spectra shows that the spectral characteristics of leaf samples are not compatible with the ones obtained from canopy level. Although moisture content of vegetation can be influential to the radiant flux reflected from leaf-level, it may not be very straightforward to obtain the spectral characteristics that are directly related to the level of canopy moisture content. Canopy spectra form forest stands can be varied by structural variables (such as LAt, percent coverage, and biomass) other than canopy moisture content.

• Journal of Biosystems Engineering
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• 제35권2호
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• pp.132-137
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• 2010

Site-specific N application for corn is one of the precision crop management. To implement the site-specific N application, various nitrogen stress sensing methods, including aerial image, tissue analysis, soil sampling analysis, and SPAD meter readings, have been used. Use of side-dressing, an efficient nitrogen application method than a uniform application in either late fall or early spring, relies mainly on the capability of nitrogen deficiency detection. This paper presents map-based variable rate nitrogen application based using a multi-spectral corn nitrogen deficiency(CND) sensor. This sensor assess the nitrogen stress by means of the estimated SPAD reading calculated from the corn leave reflectance. The estimated SPAD value from the CND sensor system and location information form DGPS of each field block was combined into the field map using a ArcView program. Then this map was converted into a raster file for a map-based variable rate application software. The relative SPAD (RSPAD = SPAD over reference SPAD) was investigated 2 weeks after the treatments. The results showed that the map-based variable rate application system was feasible.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.418-421
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• 2007

Using gridded wind-stress products constructed by satellite scatterometers (ERS-1, 2 and QSCAT) data and those by numerical weather prediction(NWP) model(NCEP-reanalysis), we estimate wind-driven transports of the North Pacific subtropical gyre, and compare them in the central portion of the gyre (around 300 N) with geostrophic transports calculated from historical hydrographic data (World Ocean Database 2005). Even if there are some discrepancies between the wind-driven transports by the QSCAT and NCEP products, they are both in good agreement with the geostrophic transports within reasonable errors, except for the regional difference in the eastern part of the zone. The difference in the eastern part is characterized by an anticyclonic deviation of the geostrophic transport resulting from an anti-cyclonic anomalous flow in the surface layer, suggesting that it is related to the Eastern Gyral produced by the thermohaline process associated with the formation of the Eastern Subtropical Mode Water. We also examine the consistency of the Sverdrup transports estimated from these products by comparing them with the transports of the western boundary current, namely the Kuroshio regions, in previous studies. The net southward transport, based on the sum of the Sverdrup transports by QSCAT and NCEP products and the thermohaline transport, agrees well with the net northward transport of the western boundary current, namely the Kuroshio transport. From these results, it is concluded that the Sverdrup balance can hold in the North Pacific subtropical gyre.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2008년도 Proceedings of the Convention
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• pp.103-115
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• 2008

Hemodynamic shear stress, the dragging force generated by blood flow, is known as an anti-atherogenic factor. We tested whether lysyl-tRNA synthetase (KRS) will be utilized as an agent controlling shear-sensing systems. KRS was previously known to be secreted as a pro-inflammatory agent. Here we found that KRS inhibited various shear-stimulated signaling pathways. We further found that KRS binds to detergent-resistant membrane (DRM), indicating that KRS binding molecules exist in DRM, specialized regions of the plasma membrane. DRM plays important roles in a variety of cellular processes and consists of gangliosides, signaling molecules and cytoskeletons. We then determined that KRS was colocalized with integrins ${\alpha}4$, ${\alpha}5$ and $av{\beta}3$. In addition, KRS was shown to be associated with sialic acid, existing at the end of gangliosides. Interestingly, the adherent effect of KRS was inhibited by pretreatment with sialic acid. Moreover, treatment of endothelial cells with neuraminidase appeared to inhibit both the KRS adhesion to endothelial cells and shear-stimulated signaling. In conclusion, KRS is likely to be utilized as a vascular regulator.